Anthelmintic 1-cinnamamido-2,4-imidazolidinediones.

A series of 1-(substituted cinnamamido)-2,4-imidazolidinediones has been prepared from the corresponding cinnamoyl chlorides and 1-amino-2,4-imidazolidinedione hydrochloride in pyridine. These compounds possess a significant degree of anthelmintic activity against the mouse pinworm Syphacia obvelata. The most active compounds are those substituted with halogen or cyano groups.